Thank you.  Setting the enemy AI to beginner effectively did the trick.

I have never been able to finish several of the more difficult quests (std and mod) before the game ends with the death of the last enemy.  Guess I could just ignore them, but it's a PITB!

An easy way to do this is to create a starting empire at begainer, and set the turns in elementaldef to  9000000. It's under sov rulesset. They have a nice comment, you can't miss it. It will give you a near endless game where the enemy will not fight you. Another is create a map where the enemy starts on an island thats unreachable, with just 1 food resources. I also think you might be able to get away with setting win conditions to win by diplomacy and kill of the enemy when the game starts. Not sure if that will end the game. I haven't tested it yet.